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DS3 Congestion - Ideas on how to identify traffic flows - ideas are welcome

Currently I have a CISCO 7246VXR uBR chassis that has a direct DS3 connection using a PA-M1T-T3 and connects point to point into a GSR 12016 chassis.

Every few days around 12:00am PST, the rx load on the interface (S1/0) goes up to 253/255, while the tx load stays around 24/155.

The entire DS3 is saturated with inbound trafic during a specific time period and I suspect this may be someone running a backup or data base archive over the DS3 from a cable modem host.

Here is the show interface S1/0:

Serial1/0 is up, line protocol is up

Hardware is M1T-T3 pa

Internet address is

MTU 4470 bytes, BW 44210 Kbit, DLY 200 usec,

reliability 255/255, txload 24/255, rxload 253/255

Encapsulation HDLC, crc 32, loopback not set

Keepalive set (10 sec)

Restart-Delay is 0 secs

Last input 00:00:00, output 00:00:00, output hang never

Last clearing of "show interface" counters 1d22h

Input queue: 0/2046/0/6125 (size/max/drops/flushes); Total output drops: 79087629

Queueing strategy: fifo

Output queue :0/2046 (size/max)

5 minute input rate 43962000 bits/sec, 5605 packets/sec

5 minute output rate 4277000 bits/sec, 4918 packets/sec

616732802 packets input, 1105854862 bytes, 0 no buffer

Received 0 broadcasts, 0 runts, 0 giants, 0 throttles

0 parity

4 input errors, 0 CRC, 0 frame, 4 overrun, 83 ignored, 0 abort

631574427 packets output, 3813633369 bytes, 17 underruns

0 output errors, 0 applique, 0 interface resets

0 output buffer failures, 0 output buffers swapped out

0 carrier transitions

rxLOS inactive, rxLOF inactive, rxAIS inactive

txAIS inactive, rxRAI inactive, txRAI inactive

I am looking for suggestions on how to identify the types of traffic over the DS3 to track down any particular hosts that may be over utilizing the DS3 so I can rate-limit their usage.

Please offer any ideas you can think of,


Re: DS3 Congestion - Ideas on how to identify traffic flows - id

You can configure 'ip route-cache flow' on your T3 interface and after that view the traffic flows with the 'show ip cache flow' commnad. You will figure out very easy which traffic flow is congesting your T3 link.



Re: DS3 Congestion - Ideas on how to identify traffic flows - id

on the remote end turn on ip accounting , Ip accounting only collects data outbound, this is why it needs to be on the remote end .

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